We report on studies aimed to evaluate the effects of five nematophagous fungi on population dynamics of northern root knot nematode, Meloidogyne hapla and sugar beet cyst nematode, Heterodera schachtii in laboratory and greenhouse trials. During our biocontrol studies, mainly five fungal species Arthrobotrys oligospora, Dactylella oviparasitica, Clonostachys rosea, Stropharia rugosoannulata, and Lecanicillium muscarium were isolated from eggmasses of nematodes during root and soil samples collected in Czech Republic and tested against Meloidogyne hapla in carrots while Heterodera schachtii in sugar beet, both in-vitro and in-vivo fashions. All fungi exhibited varied type of infection on nematodes but L. muscarium proved to be the most potential bioagent in controlling nematode population enormously. Lecanicillium muscarium not only halted nematode reproduction factor (Pf/Pi) but also escalated plant growth. Plant root systems treated with L. muscarium were observed colonized by fungi while seen under microscope which depicted that fungi provided a protecting shield or body guard against plant parasitic nematodes. Moreover, L. muscarium was further compared with commercially available nematicides and a fertilizer to justify its highly potential for diminishing nematode population. L. muscarium along with nematicides and fertilizer had dramatic effects in reduction of both nematodes (M. hapla, H. schachtii) population in soil but improvement of plant growth was only noticed in case of L. muscarium. The chemical nematicide, Dazomet had some negative effects which appeared in the form of chlorotic spots on leaves which further suggested that there were some the phytotoxic effects.

Submitted by (edna.saturno@ufrpe.br) on 2016-11-24T16:39:07Z No. of bitstreams: 1 Jose Menezes Araujo Junior.pdf: 362260 bytes, checksum: ad127ee31030ace5f6a04e4c2c1df8cb (MD5) / Made available in DSpace on 2016-11-24T16:39:07Z (GMT). No. of bitstreams: 1 Jose Menezes Araujo Junior.pdf: 362260 bytes, checksum: ad127ee31030ace5f6a04e4c2c1df8cb (MD5) Previous issue date: 2008-02-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The aphid, Lipaphis erysimi (Kalt.) (Hemiptera: Aphididae), is considered an important pest of kale in Brazil. Botanical insecticides and the fungi Metarhizium anisopliae (Metsch.) Sorok., Beauveria bassiana (Bals.) Vuill., and Lecanicillium muscarium (Petch) Zare & Gams are promising alternatives to control aphids populations. This work aimed to evaluate isolates of entomopathogenic fungi and toxicity of the neem formulation (Neemseto®) to control L. erysimi, as well the compatibility of the selected isolates and neem oil. Survey done accros kale areas from five counties of the Agreste region in Pernambuco State resulted in presence of L. erysimi in four of them. Among 20 evaluated fungi isolates, the B. bassiana CG 001 and M. anisopliae CG 30 were the most pathogenic, providing 90 and 64% mortality towards the aphid, respectively. The CL50s for B. bassiana CG 001, M. anisopliae CG 30, and L. muscarium URPE-24 were 1,6x106,3,4x106 and 2,5x105 conidia mL-1, respectively. Bioassays with the neem formulation at concentrations 0.5, 1.0, and 2.0% were done either by leaf discs dipping or spraying the aphids on the leaf discs. All treatments caused mortality higher than 60 %, however the neem spraying treatment at 2.0% provided 90% mortality. Regarding the compatibility of B. bassiana CG001, M. anisopliae CG30 isolates with the neem oil formulation at 0.125, 0.25, and 0.5%, the 0.5% treatment did not affect the B. bassiana CG 001 viability. Compatibility test conducted with theisolates CG001 of B. bassiana and CG30 of M. anisopliae with Neemseto® at concentration 0.125, 0.25 and 0.5%, showed that the highest neem concentration caused negative impact on sporulation of the isolate CG001 and on vegetative growth and viability of the isolate CG30. These results show that the isolates B. bassiana CG001, M. anisopliae CG 30, L. muscariumURPE-24, and neem oil may be used to the control of L. erysimi. / O pulgão Lipaphis erysimi (Kalt.) (Hemiptera: Aphididae) tem-se destacado como praga das brássicas. Entre as medidas de controle de pulgões, o uso de Metarhizium anisopliae (Metsch.) Sorok., Beauveria bassiana (Bals.) Vuill. e Lecanicillium muscarium (Petch) Zare & Gams, e de extratos de plantas têm sido considerado uma alternativa promissora. Assim, este trabalho objetivou selecionar isolados de fungos entomopatogênicos eficazes e estudar a aplicação de nim formulado para controle de L. erysimi e avaliar também, a compatibilidade entre os isolados e o nim. Levantamentos realizados em cultivos de brássicas, no Agreste de Pernambuco, mostraram que L. erysimi ocorreu em quatro das cinco localidades investigadas. Foram avaliados 20 isolados de fungos, onde CG001 de B. bassiana e CG30 de M. anisopliae apresentaram-se como os mais patogênicos causando 90 e 64% de mortalidade, respectivamente. Para a determinação da concentração letal (CL50) foram utilizou-se estes dois isolados e URPE-24 de L. muscarium. Osvalores para a CL50 foram de 1,6 x 106, 3,4 x 106 e 2,5 x 105 conídios mL-1, para B. bassiana, M. anisopliae e L. muscarium, respectivamente. O óleo de nim formulado foi testado em três concentrações (0,5; 1,0 e 2,0%) por imersão foliar e pulverização sobre os pulgões. Em todos os tratamentos observou-se mortalidade superior a 60%, porém o melhor resultado foi obtido com apulverização do nim a 2,0% proporcionando mortalidade de 90%. Testando a compatibilidade in vitro de CG001 de B. bassiana e CG30 de M. anisopliae com o Neemseto® a 0,125; 0,25 e 0,5%, observou-se que o tratamento a 0,5% afetou apenas a esporulação do isolado CG001 e o crescimento vegetativo e a viabilidade de CG30. Pode-se concluir que os isolados CG001, CG30 e URPE-24 de B. bassiana, M. anisopliae e L. muscarium, respectivamente, e óleo emulsionávelde nim podem ser utilizados para o controle de L. erysimi.

This diploma theses focuses on comparison of natural and intentionally inducated supressiveness of environment induced by application of entomopathogenic fungi Beauveria bassiana, Metarhizium anisopliae, Isaria fumosorosea a Lecanicillium muscarium. In tests were evaluated the in vitro parameters as well as the effectiveness in vivo biotests on insect host larva Tenebrio molitor. The species of entomopatoghenic fungi were applied in suspensions, single strains and also in combination of two strains. In the in vitro conditions the possibilities of objective evaluation of the supresivity level were tested by using the CFU test (Colony Forming Units) on three different nutrient media (PDA, PDA + A , PDA + D), as one of the basic evaluation parameters. Further the germination tests were evaluated according to GI (Germination Index), determination of radial growth (comparison of median cultures) and interaction of strain suspensions on nutrient media PDA. In the in vivo biotests were watched the epizooties from suspensions of these entomopathogenic fungi on insect larva Tenebrio molitor in competitive test of strains according to FDI (Fungl development index) evaluation scala. Chosen larva covered by fully sporulating mycelium from epizootie were further evaluated in CFU test. The result were dominant strain/s on the larva from applied suspensions.